E484K and N501Y SARS-CoV 2 spike mutants Increase ACE2 recognition but reduce affinity for neutralizing antibody

Int Immunopharmacol. 2022 Jan:102:108424. doi: 10.1016/j.intimp.2021.108424. Epub 2021 Dec 3.

Abstract

SARS-CoV2 mutants B.1.1.7, B.1.351, and P.1 contain a key mutation N501Y. B.1.135 and P.1 lineages have another mutation, E484K. Here, we decode the effect of these two mutations on the host receptor, ACE2, and neutralizing antibody (B38) recognition. The N501Y RBD mutant binds to ACE2 with higher affinity due to improved π-π stacking and π-cation interactions. The higher binding affinity of the E484K mutant is caused due to the formation of additional hydrogen bond and salt-bridge interactions with ACE2. Both the mutants bind to the B38 antibody with reduced affinity due to the loss of several hydrogen-bonding interactions. The insights obtained from the study are crucial to interpret the increased transmissibility and reduced neutralization efficacy of rapidly emerging SARS-CoV2 VOCs.

Keywords: ACE2 binding; Antibody binding; Binding free energy; Hydrogen bonds; RBD mutations; π-π and π-cation interactions.

MeSH terms

  • Angiotensin-Converting Enzyme 2 / metabolism*
  • Angiotensin-Converting Enzyme 2 / ultrastructure
  • Antibodies, Neutralizing / metabolism*
  • Antibody Affinity / genetics
  • Binding Sites / genetics
  • Crystallography, X-Ray
  • Humans
  • Mutation
  • SARS-CoV-2 / genetics
  • SARS-CoV-2 / immunology
  • SARS-CoV-2 / pathogenicity*
  • Spike Glycoprotein, Coronavirus / genetics*
  • Spike Glycoprotein, Coronavirus / immunology
  • Spike Glycoprotein, Coronavirus / metabolism
  • Spike Glycoprotein, Coronavirus / ultrastructure
  • Virus Internalization

Substances

  • Antibodies, Neutralizing
  • Spike Glycoprotein, Coronavirus
  • spike protein, SARS-CoV-2
  • ACE2 protein, human
  • Angiotensin-Converting Enzyme 2

Supplementary concepts

  • SARS-CoV-2 variants